FIG. 1 illustrates a conventional printed wiring board (PWB) or printed circuit board (PCB) 10 including bus wiring for linking or connecting semiconductor chips mounted thereon. Each semiconductor chip 12, 14, and 16 is coupled to PWB 10 via wire buses 18. Conductive joints between each chip and the PWB 10 are formed by permanently soldering the pins of each chip to wire buses 18. This approach of connecting chips is subject to a large number of manufacturing defects, particularly in the solder bonds, increasing the overall cost of the manufacture and decreasing the reliability of the PWB 10. While not shown explicitly within FIG. 1, the semiconductor chips 12, 14 and 16 can be mounted on a surface layer of the PWB 10, can be connected via wires to a power plane layer (i.e., for power voltage connections) and can be further connected via wires to a ground plane layer (i.e., for ground voltage connections). Each layer may be stacked or mounted on a substrate of the PWB 10.
FIG. 2 illustrates a top-view of a conventional PWB 200 for facilitating wireless communication between a plurality of semiconductor chips mounted thereon. As shown in FIG. 2, the PWB 200 includes a plurality of chips 20, 22, and 24 that are physically spaced apart on a surface layer of the PWB 200. Each chip 20, 22, and 24 includes a transmitter 30, a receiver 40 and an antenna unit 50. During operation of the PWB 200, information processed by chips 20, 22 and/or 24 is outputted by that chip's respective transmitter 30. Transmitter 30, being coupled to antenna unit 50, transmits its chip's information processed in the form of electromagnetic energy into the free space area around chips 20, 22, and 24. After a given transmitter 30 of a given chip transmits a wireless signal, a receiver 40 at one or more other chips receives, through antenna unit 50, the transmitted information. The information received by receiver 40 is then transferred into the chip for further processing.
In order to accomplish the above-described wireless transmission and reception of FIG. 2, each transmitter 30 and receiver 40 (“transceiver 30/40”) operates in accordance with a given wireless communication protocol (alternatively referred to as wireless communication signaling), such as an amplitude modulation (“AM”) scheme operating at different carrier frequencies. Under the AM scheme, each distinct carrier frequency can be within the operative radio frequency spectra. The wireless communication protocol used by the transceiver 30/40 may alternatively employ frequency modulation, phase shift key modulation, frequency shift key modulation, or multiphase frequency shift key modulation. The wireless communication protocol used by the transceiver 30/40 may alternatively include time division multiplexing and/or a coding scheme (e.g., Walsh codes).
As will be appreciated by one of ordinary skill in the art, the wireless transmissions at each antenna 50 of each chip can increase interference at both (i) other chips of the PWB 200 and (ii) electronic devices in proximity to the PWB 200.
Conventionally, the entire PWB 200 can be shielded with a metal housing (not shown) in order to reduce type (ii) interference. The metal housing reduces stray electromagnetic radiation as well as unintended coupling of energy generated by other systems (not shown) from interfering with operation of the PWB 200. However, type (i) interference can remain problematic in conventional wireless chip-to-chip communication systems.